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    <title>ShellCheck: SC1087 – Use braces when expanding arrays, e.g. `${array[idx]}` (or `${var}[..` to quiet).</title>
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    <h1>SC1087 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC1087">See this page on GitHub</a>
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    <h2
id="use-braces-when-expanding-arrays-eg-arrayidx-or-var-to-quiet">Use
braces when expanding arrays, e.g. <code>${array[idx]}</code> (or
<code>${var}[..</code> to quiet).</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC1087.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;</span><span class="va">$array</span><span class="st">[@]&quot;</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC1087.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;</span><span class="va">${array</span><span class="op">[@]</span><span class="va">}</span><span class="st">&quot;</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>Some languages use the syntax <code>$array[index]</code> to access an
index of an arrays, but a shell will interpret this as
<code>$array</code> followed by the unrelated literal string (or glob)
<code>[index]</code>.</p>
<p>Curly braces are needed to tell the shell that the square brackets
are part of the expansion.</p>
<h3 id="exceptions">Exceptions</h3>
<p>If you want the square brackets to be treated literally or as a glob,
use <code>${var}[idx]</code> to prevent this warning.</p>
<p>This does not change how the script works, but clarifies your intent
to ShellCheck as well as other programmers.</p>
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    <p style='font-size: 80%'><a href="../index.html">ShellCheck</a> is a static analysis tool for shell scripts. This page is part of its documentation.</p>
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